(2) Upwards compatibility: When people upgraded from a 286/386/486 they went to a machine that could still run all the old software. So there was no point in hanging on to the old computer. Contrast this to when you upgraded from a C64, Apple or similar to a PC clone (or Mac). Rather than bin, better to shove that beloved beast in the cupboard just in case in a fit of nostalgia you wanted to revisit those glory days (your shiny new machine wasn't gonna do it). Nostalgia saved the old 8-bitters from the trash.

(3) Y2K throwout: The Y2k scare who saw a HUGE number of 486 machines and below simply scrapped...particularly from businesses. I remember scrapping a few at work. There was talk about just "officially" giving them away but the bureaucracy and paperwork involved was too much. Also, Health and Safety laws meant that we were liable for anyone who electrocuted themselves playing with these old machines. Hard drives were formatted with a hammer then they just got chucked.

(4) Size: A C64 or a ZX-Spectrum is small enough to put in a box in a wardrobe and forget. Not so a fully decked out 286/386/486

Yeah, agreed on all fronts. At once time you could trip over 386s on the footpath but now... now they are scarce indeed. I think in my personal collection I have two working 486s and a single working 386. Pentiums and stuff are a little more easily found but anything pre-Pentium is really unusual to see. But enough about that, we should probably stop hijacking this Apple II thread

Just the local Commodore hobo and middle-aged PC hoarder.eisa on Trademe. A lasting reminder of a Compaq fetish when I was younger.

I'd wager it's more likely to be a Pentium II. 24x CDROM, no turbo switch (unlikely someone would have put a 386 motherboard in a modern AT case).I have got all my 286, 386 , and 386 machines for $20-50, but I haven't seen one in ages :S Finding those old generic AT cases is a nightmare too.

I have it running now, which is great news! Those 74LSxxx chips can be fragile...but now I have another issue - and this one is odd. Disk drives.

I have 3x 5.25 (half height) drives. I now have 20+ 2DMD disks, but no matter what I do, none will format. I always get a "Check disk or Drive Door" in ADTPro 1.26. I have had each drive connected to the Apple with exactly the same issue on each drive.

Things which have been tried:- Disassembled the drives and cleaned the heads and rails- Checked the drive belts- Changed the controller (I have 5 of these cards)- Tried slot 6 and 7

Every time it goes through the motions of formatting - and then as it is finishing, i get the "Check disk..." error. If I try to send a .dsk over to the drive it gives write errors on each sector (which I expected on disks which aren't formatted)

Any ideas?

I'm not sure where to go from here as everything seems to be fine...but isn't...

Strange. I've never really had any problems with ADTPro, formatting etc. If all the drives and controllers are showing the same behaviour, I'd have to suspect the disks. They are 1D or 2D, right, not HD '1.2MB' types?

Edit: I see you say 2DMD. That's not a type I'm familiar with. Are you sure the density (coercivity) is OK? I know the range of coercivity in 5.25 inch disks is pretty wide, so it's pretty vital to use the right type.

Things which have been tried: <disky things removed>- Changed the controller (I have 5 of these cards)- Tried slot 6 and 7

...and this troubleshooting relates to the Apple end of things?

Now, I seem to recall that the mighty Woz did cunning things with the Apple disk controller, there is a good chance that the PC drives just don't cut the mustard for this application.Could you perhaps just confirm what the hardware connections are?Are you using ADT on a PC to write the disks and getting the errors, or writing 'successfully' on the PC then trying them in the Apple and getting the error responses, or are you using ADT on the Apple where these errors are appearing? Have you tried using one of your other ][s as a guinea pig?

On the underside of the drive is a set of calibration marks. Just set up a light, ran the drive and it was out. I have 1 drive working now - so I'm going to try using Copy II+ to calibrate the other two.

Hmm, I'd be surprised if the drive speed would cause format failures unless it's really way off. Surely all three drives wouldn't have failed like that? I haven't fiddled much with the aftermarket half-height type drives, but I do have a number of them, and the failure modes seem about the same as the Disk 2 - dirty heads, alignment, dead analogue board due to having been plugged in incorrectly (only the header-type ones of course, not the later D-shell connector Unidisk style ones). You've ruled out the first, the second wouldn't cause format problems, the third is certainly possible. Do all your interface cards show the same behaviour? They could all have failed in the same way (especially if someone's done something nasty to them) but it doesn't sound likely. Terry reckons the disks are OK, and I'd certainly accept his word on that. So my next question would be - do your drives have the inline header type connector, or the D-shell one? If they have the header type, do you know what the chances are of someone having damaged all three by plugging them in back to front or a pin or two offset?

If you get really stuck, maybe you can find someone with a known good Apple setup who can test them? I'd be happy to, but I'm a bit far away.

falco wrote:Hmm, I'd be surprised if the drive speed would cause format failures unless it's really way off. Surely all three drives wouldn't have failed like that? I haven't fiddled much with the aftermarket half-height type drives, but I do have a number of them, and the failure modes seem about the same as the Disk 2 - dirty heads, alignment, dead analogue board due to having been plugged in incorrectly (only the header-type ones of course, not the later D-shell connector Unidisk style ones). You've ruled out the first, the second wouldn't cause format problems, the third is certainly possible. Do all your interface cards show the same behaviour? They could all have failed in the same way (especially if someone's done something nasty to them) but it doesn't sound likely. Terry reckons the disks are OK, and I'd certainly accept his word on that. So my next question would be - do your drives have the inline header type connector, or the D-shell one? If they have the header type, do you know what the chances are of someone having damaged all three by plugging them in back to front or a pin or two offset?

If you get really stuck, maybe you can find someone with a known good Apple setup who can test them? I'd be happy to, but I'm a bit far away.

I've got 3 IIe machines - and the drives do the same thing on all 3. I do have a working drive now - one of then was spinning at 150ms when the operating range was 198-202ms. Turn the speed adjustment screw until it read around 200ms - works fine. Now I can use Copy II+ to read the speeds of the other two drives.

The other two have fluctuating speeds in Copy II+, apparently this can also just be dirty heads - but these are very clean.

Terry's disks are all spot on - I have used a few already and they are great. The drive types are the 1/2 height 5.25 versions with the D-shell connector, so unlikely they were plugged in the wrong way, but they may have been unplugged while still running.

Time to swap boards from the good drive etc and narrow down where the issue is. There are 2 boards in these drives. Nice way to spend a sunday afternoon I must say...

Gibsaw wrote:Out of curiosity, which 74LSxxx did you strike the problem with?

After several reboots and changing socketed chips, I thought it better that I look at the schematic and figure out the boot sequence. In the end I socketed and put new 74LS244 (x2), the 245 and the 374 - and away she goes...